russell-clarke



Oct. 23 1923. I 1,471,684

E. RUSSELL-CLARKE CALCULATING MACHINE Filed Dec. 9, 1919 14 Sheets-Sheet 1 w a I Oct. 23 1923. 1,471,684

E. RUSSELL-CLARKE CALCULATING MACHINE Filed Dec. 9, 1919 14 Sheets-Sheet 2 Oct. 23, 1923. 1,471,684

E. RUSSELL-CLARKE CALCULATING MACHINE l4 Sheets-Sheet 5 Filed Dec. 9, 1919 Oct. 23. 1923. 1,471,684

E. RUSSELL-CLARKE CALCULATING MACHINE Filed Dec. 9, 1919 14 Sheets-Sheet 4 Oct. 23 1923. 1,471,684

E. RUSSELL-CLARKE CALCULAT ING MACHINE Filed Dec. 9, 1919 14 Sheets-Sheet 5 M WMM/ Oct. 23, 1923. 1,471,684

E. RUSSELL-CLARKE CALCULATING MACHINE Filed Dec. 9, 1919 14 Sheets-Sheet 6 Oct. 23, 1923. 1,471,684

E. RUSSELL-CLARKE CALCULAT ING MACHINE Filed Dec. 9, 1919 14 Sheets-Sheet '7 EM 3- KM.

Oct. 23, 1923. 1,471,684

E. RUSSELL-CLARKE CALCULATING MACHINE Filed Dec. 9, 1919 14 Sheets-Sheet 8 jaw.

Q *4 (PM E. RUSSELLCLARKE CALCULAT ING MACHINE Filed Dec 9, 1919 14 Sheets-Sheet 9 Oct. 23 1923.

E. RUSSELL-CLARKE CALCULATING MACHINE FiledDe. 9, 1919 14 Sheets-Sheet 10 Oct. 23, 1923.

- E. RUSSELL-CLARKE CALCULATING MACHINE 14 Sheets-Sheet 1] Filed Dec. 9, 1919 Oct. 23, 1923.

E. RUSSELL-CLARKE CALGULAT ING MACHINE Filed Dec. 9, 1919 14 Sheets-Sheet 12 E. RUSSELL-CLARKE CALCULATING MACHINE Filed Dec. 9,1919 14 Sheets-Sheet 15 E. RUSSELL-CLARKE CALCULATING MACHINE Oct. 23, 1923. 1,471,684

Filed Decf9, 1919 14 Sheets-Sheet 14 Patented Oct. 23, 1923.

UNITED STATES PATENT OFFICE.

EDWARD RUSSELL-CLARKE, DECEASED; BY

FRANCES MAUD RUSSELL-CLARKE, EX-

ECU'IRIX, OF LONDON, ENGLAND, ASSIGNOR T0 AUTOKAL SYNDICATE LIMITED, OF

LONDON, ENGLAND.

CALCULATING MACHINE Application flied December 9, 1919. Serial No. 343,680.

To all whom it may concern Be it known that I, Mrs.) FRANCES MAUI) RUssELL-CLARK'E, a subject of the King of Great Britain, and residing at London, in England, sole executrix of EDWARD Rossett- CLARKE, late a subject of the King of Great Britain, who invented certain new and useful Improvements in Calculating Machines, of which the following is a specification.

This invention relates to calculating machines more especially those for performing addition or subtraction and has for its object to simplify the construction of such machines and to produce a machine which may either he used separately or combined with acalculating machine of another type for example one which is adapted for the performance of multiplication.

According to this invention the machine is built up of a series of co-operating me chanical units each comprising a pair of pivotally mounted concentric sectors one toothed on its concave side and the other toothed on its convex side. A double pinion carrying a numbered wheel is so mounted on a movable member that the pinion can be brought into engagement with either of the sectors the number wheel being locked against rotation except when the pinion and a sector are engaged. Each pair of sectors can beset or positioned in accordance with the value of an item fed into the machine and after being so set the pinion of a number wheel is brought into engagement with one or other of the sectors according to whether addition or subtraction is to be performed and the sector is then moved back to its zero point in so doing rotating the number wheel to the extent determined by the original setting of the sector. The limit of movement of each sector in. a zero direction is. determined by a removable stop and when a number wheel has been. rotatedbeyond a carry point it operates a trigger which brings about the removal of the stop limiting the movement of the sectors in the mechanicai unit of next highest denomination. Thus when these sectors are returned towards their zero point they can move past I this point to the extent of one integer and in so doing rotate the number Wheel controlled by them to the extent of one additional integer as required by the carry.

The several units which make up the complete machine are disposed side by side so that they can be controlled simultaneouslv by rock shafts, levers and bars actuated by rotating cams. Certain of these cams are constantly acting but three other cams are provided which can be alternatively clutched to the main shaft for the purpose of actuating the mechanism in accordance with Whether the machine is to be used for performing addition or subtraction or if it is to be cleared, that is to say if any existing sum which may be set up is to be wiped out and the number wheels restored to zero.

After an item has been fed into the ma chine in some convenient manner the mechanism is actuated and performs a cycle. When the parts are in their initial positions at the commencement of a cycle each number wheel pinion is in engagement with its outer or addition sector. At the beginning of the cycle the plates or other members carrying the number wheels are lowered the pinions being thereby removed out of engagement with the addition sectors and locked. Simultaneously all the carry de vices are reset. The sectors are now al simultaneously released and fall freely into the positions determined by the keys or other mechanisms which have been operated in the process of feeding the item into the machine. The first half of the cycle is now complete. The second half of the cycle commences with the simultaneous movement of all the number wheel plates upwards or downwards according as addition or subtraction is to be performed the number wheel pinions thus being brought into engagement with their respective sectors. All the sectors are now moved back again to their zero positions and as they move they rotate the number wheels, the necessary carries taking place during this process. The result of the sum performed is now exhibited and the cycle is completed.

The accompanying drawings iiiustrate one form of a machine constructed in accord mice with this invention. This machine is arranged for dealing with money sums and has a capacity extending from one penny up to 9,999.19l1.

Figure 1 and Figure 1 together show an elevation of the front of the mach ne the left hand portion appearing in Figure l and, the right hand portion in Figure 1*.

Figure 2 is an elevation of the right hand side of the machine as viewed in Figure 1, the external gear wheels being removed.

Figure 3 is a side elevation of the mechanism comprised in one of the units the view being taken from the right hand side of the machine.

Figure 4 illustrates the carry mechanism. and is a side elevation of part of ti mechanism comprised in a unit, the Jew being taken from the left hand side of the machine as shown in Figure 1. The carry mechanism is here shown in its set position.

Figure 5 is a plan of the mechanism shown in Figure Figure 6 is a section on the line 66 of Figure l looking in the direction of the arrows and illustrates on a larger scale a de' tail of the carry mechanism.

Figure 7 is a view similar to Figure 4- illustrative of the operation of the carry mechanism and showing this mechanism when the carry lever has been released.

Figure 8 is again a view similar to Figure a showing the resetting of the carry mechanism.

Figure 9 is a erspective view showing one of the sector levers and the manner in which it is mounted for the purpose of permitting the movement which results when a carry takes place.

Fi ure 10 is aside elevation taken from the right hand side of the machine showing the construction and arrangement of the sector which deals with thousands of pounds.

Figure 11 is a part sectional view on the line ll11 of Figure 10 looking in the direction of the arrow.

Figure 12 is a side elevation of the main operating cams.

Figure 13 is a side elevation of another cam.

Figure la is a section on line let-1 l of Figure 155 Figure 151s a )lan view of the mechanism for intermittent y connecting the pulley X and shaft T, which mechanism is illustrated in elevation at the right hand end of Figure 1;

Figure 16 is a section similar to Figure 14 but showing the parts in a different position;

Figure 17 is a perspective view of one of the cams included in the machine and its associated mechanism;

Figure 18 is a perspective view of another cam together with the parts immediately operated thereby;

Figures 19, 20 and 21 are also perspective views of certain of the cam members of the mechanism together with the mechanism operated thereby.

Figs. 2 and 23 show respectively side and front elevations of the pence number wheel; and

Figs. 2a and 25 show similar views of the tens of shillings numher wheel.

Like letters indicate like parts through-- out the drawings,

As the principal parts comprised in a unit mechanism are most clearly shown in Figures 3, at and 5 it is convenient first to refer mainly to those figures but many of the parts may also he seen in their relative positions in the several unitsin Figures 1 and 2.

The curved toothed sectors A and B are both mount-ed concentrically on the outer part C of a lever which conveniently forms an angle with the part C adjacent to the shaft C on which the lever can turn. On the end of the lever C C is disposed a curved plate C on the outer face of which numbers are engraved. Towards the upper part of the back of the side frames D on a bracket D fixed to a horizontal frame member D is pivoted a lever in the form of a plate E which is inclined from its p'vot E towards the front of the machine. The free end of this plate E is forked as at 4 2 to engage a pin F on the end of a lever F keyed on a shaft F whose ends are carried in hearings in the frame members D. A lever F also keyed on the shaft F is directed towards the rear of the machine and has connected to it one end of a spring F whose other end is attached to the frame. On a stud E projecting from one side of the plate E is mounted a double pinion G G. That portio'n G of this pinion which has the larger diameter has teeth adapted to engage the outer toothed rack A which rack operates for the purpose of performing additiom The smaller part G of the pinion has teeth adapted to engage the inner rack B which performs theoperation of subtraction. Connected to the double pinion G G is a number wheel comprising spokes G and a pcripheral flange i which is directed towards the face of the plate E as clearly shown in Figure 5. In the flange G are formed a series of equidistant notches G, which alter nate with numbers which are engraved on the face of the flange. One. of these notches is cut somewhat deeper and in it lies the end of a lever G pivoted at G on one of the spokes, of the number wheel and controlled by a spring G which tends to keep the end of the lever G projecting through the opening in the flange G The number wheels have somewhat different constructions according to the value of the amounts they have to deal with. Thus the pence number wheel which is the right cumference.

' sides of the lever E.

hand wheel in Figure 1 and is also shown separatel in Figures 22 and 23 has 12 notches Cir in its flange instead of 10 as in the other wheels. The tens of shillings number wheel, that is the left hand wheel of F igure 1, has 10 notches G in its flange but is provided with five carry projections G which are equally spaced around its cir- This number wheel is also shown separately in Figures 24 and 25. The remaining number wheels serving respectively for units of shillings, units of pounds, tens of pounds, hundreds of pounds and thousands of pounds are all similar and arranged in the manner shown in Figures 4 and 5, except that the thousands of pounds wheel has no carry projection G'.

On the same side of the plate E as the number wheel and adjacent to the flange G thereof is pivoted at E a lever having two arms one of which E lies parallel to the face, of the plate E and is upwardly directed, its upper end being bent over to overlie the edge of the plate E while the other E isbent over at right angles and asses through a uadrantal slot E formed 1n the plate E. be end of the lever E projects through this slot on the opposite side of the plate E (see Fi re 6). Between the lever E and the face of the plate E is pivoted at E a small plate E which has a projecting arm or detent E and carries on its face two lateral projections E and E which normally lie close to the The detent E lies beside the edge of the flange G of the number wheel in such a position that when this wheel rotates beyond a certain point the detent E will be struck by a pin G which projects laterally from the edge of the flange G as shown in Figure 5. -The point in the rotation of the number wheel when the pin G strikes the detent E is termed the carry point. A spring E" is connected at one end to the end of the lever E and at the other to some flexed point on the plate E. The action of this spring tends to keep the lever E in contact with the" two projections E and E thereby maintainmg the detent E in a mid-position but permitting it and the plate E to turn in either direction about its pivot. As the number wheel rotates past the carry point the detent E is moved about its pivot by the pin Gr and snaps over this pin. The movement thus imparted to the plate E is communicated through either the projection E 'or the projection E to thelevers E", E as shown in F i re 7, according to the direction of rotation of the number wheel and the direction in which it moves the detent E. v

Pivoted at E on the side of the plate E remote from the number wheel is a threearmed lever. The longest of these arms H is forwardly directed and lies beside the face of the plate E with its end over the projecting end of the lever E. .A second arm is directed towards the rear of the machine and carries a lateral projection H as shown in Figures 4 and 5. A third arm H is upwardly directed and has connected to it one end of a spring H the other end of which is attached to some fixed point on the plate E. It will be seen that so long as the detent E remains in its mid-point the end of the lever E will engage the end of the lever H, and hold it in the position shown inFigure 4. If, however, the detent E is struck by the pin G as the number wheel passes a carry point the lever E will be moved clear of the end of the lever H and the latter will be caused to drop under the influence of the spring H The projection H constitutes a stop which limits the movement towards the rear of the machine of the sector lever C C in the next adjacent unit mechanism of higher denomination. There is a rearwardly directed rojection C on the part C of each sector ever which is so disposed as to engIage the projection H. When the lever which mayconveniently be termed the carry lever, has been permitted to drop by reason of the lever E having been moved clear of its end, the projection H is moved upwardly into such a position that it is clear of the sector lever projection C.

This sector lever C can then move to a further extent towards the rear of the machine the projection H entering the angle C. The position then assumed by the carry lever H is shown in Figure 7. It will there be seen that the sector lever C belonging to the unit of next highest denomination has been permitted an over movement towards the rear of the machine in consequence of the projection H having been taken out of the path of the sector lever projectionG. Thus the sector lever C can move to the extent of one integer beyond its true zero position in which it is shown in Figure 4.

The carry lever H is lifted and reset bv means of the following mechanism. In suitable bearings disposed on the underside of the horizontal frame member D is carried a rockshaft J on which are keyed'a series of two-armed levers J J 2 so spaced apart that each lever forms a portion of a unit mechanism. One of the lever arms J is upwardly directed and provided with a laterally projectin pin J 8 so placed that it can strike the un erside of the carry lever H which has a notch H formed in it to receive this pin. The lever arm J has a T-shaped end with a curved outer face J which is presented to a laterally projecting pin C carried by the sector When the carry lever H has been released and has dropped into the position shown in Figure 7 it can be lifted and reset at the appropriate time the shaft J and lover J J 2 are rocked by mechanism to be hereafter described. The pin J enters the notch H and the lever H is raised, its bevelled end pushing aside the end of the lever E, until the parts are in the positions shown in Figure 8. The pin J has here moved past and out of the notch H. At the same time the curved end J of the lever arm J has struck the pin C and pushed the sector lever C C forward into its true zero position so that the projection C on the back of the sector lever C is clear for the carry lever projection H to move down again and hold the sector lever in its zero position. (Then the shaft 5 and lever J J rock back into the positions shown in Figure l the carry lever B drops until its end rests once more on the end of the catch lever E. The resetting of the carry mechanism is now completed.

A @n a horizontal bar D forming part of the framing of the machine are disposed at intervals. according to the positions of the number wheels, a series of downwardly directed brackets D each of which carries on the side of the bracket adjacent to the number wheel a lateral projection D. The shape and dimensions of this projection D are such that it can pass freely through any one of the notches G inthe flange of the num ber wheel as this wheel is raised or lowered by the movement of the plate E about its pivot. 11" the movement of the plate E is checked at a midpoint the projection D will lie in one of the notches G and lock the number wneel against rotation. Adjacent to each bracket but positioned over the face of the flange G each number wheel is a downwardly directed plate D which can engage the end of the lever n which projects hrough the slot or notch in the flange G oi. the number wheel. iVhen this which constitutes a pawl, is in eniever gagement with the plate D the number wheel is in its zero position.

As will be seen all the plates E with the number wheels and pinions carried thereon can occupy three distinct positions according to the. movement imparted to the ends of these plates by the levers F when the shalt i is rocked. The first and normal position occupied by each plate when the parts are in their initial or zero positions i" that in which this plate is shown in Figure... and Here the free end E of the plate E has been raised to limit position in which the pinion i1. is in engagement with the outer toothed sector 5;. Erie projection D now lies within the G of the number wheel which is therefore ee in so far as obstruction by this projection D is concerned to be rotated by the movement of the toothed sector A. In the second or intermediate position the plate E is partially lowered with the result that the pinion G is removed from engagement with the toothed sector A. The plate E has not been lowered sufficiently far however to bring the pinion G into engagement with the inner toothed sector B. The plate E and the number wheel carried thereby are now in the positions shown in Figure 8 where it will be seen that the projection D has been brought into one of the notches G in the flange G of the number wheel. Thus the number wheel is locked against rotation in the position in which it has been set and remains so while neither of the pinions G or G is in engagement with a toothed sector A or B. In the third position the end-of the plate E is lowered still further to its limit position when the pinion G is in engagement with the inner toothed sector 13. The accompanying drawings do not show the parts in the position which they then occupy but they will be clearly understood from Figures 3, l and 8. As the number wheel was lowered the projection D passed through the notch G in the number wheel flange G and the latter is now therefore clear of this projection so that the number wheel can be rotated by the movement of the sector lever C C.

It will be convenient here to detail the operation of the described parts of a unit mechanism when the machine is employed for performing a sum.

As already mentioned the plate E is initially in its first or fully raised position with the pinion G in engagement with the outer toothed sector A. Assuming that an item has been fed into the machine in some convenient manner such as will be hereinafter described more in detail, it is to be noted that that pr cess involves no movement of the parts of the unit mechanisms until the actuation of that mechanism which causes the various portions of the machine to perform their several functions which bring about the desired result. It may be remarked here. however, that the feeding in of the item determines the extentto which each sector lever C C can move towards the front of the machine.

When addition is to be performed the first result of putting the actuating mecha nism into operation is to rock the shaft F so as lower the plate from its first or upper position into its second or intermediate position. As already explained this moves the pinion G out of engagement with the outer toothed sector A and locks the number wheel. by engaging the projection. D with that notch G in the number wheel flange which is presented to it. 'lhe plate E and number wheel are now in the positions shown in Figure 8. At this stage the shaft J is rocked so as to operate the lever J J and reset the carry lever H in the manner described. The sector levers C C have so far all been retained in their raised and zero positions by the action of a bar K which lies beneath all these levers and operates in a manner which will hereafter be detailed to raise the levers C C. At this stage this bar K has moved away arid all the sector levers C C are allowed to turn on the shaft C and fall towards the front of the machine. The distance that each lever C C moves is determined by the figures in the item that has been fed into the machine. The shaft F is now once more rocked so as to raise the plate E once more until the pinion G is again in enga ernent with the outer toothed sector A. inally the bar K once more lifts 'all the sector levers C C moving them back again to their zero positions. As each of these levers moves it causes rotation of the corresponding number wheel so that this wheel has now been rotated the same number of integers as the sector had reviously been allowed to fall, assuming t at no carry has taken place into that unit mechanism.

When subtraction is to be performed the initial operation of the actuating mechanism isthe same as in the case of addition namely the shaft F is rocked and the plate E is lowered from its first or upper position into its intermediate position. It is assumed of course that previously the item to be dealt with has been fed into the machine. After the pinion G has been moved out of engagement with the rack A bythe lowering of the plate E the shaft J with the lever J J is rocked so as to reset the carry lever H and return the levers C C tov zero and the bar K then is moved so as to allow the sector levers C C to fall to the determined positions. The shaft F is'now once more rocked so as to lower the plate E still further and bring the pinion G intoengagement with the inner toothed sector B. The bar K isnow moved back again so as to lift the sector levers C C and return them to their zero positions this movement causing the rotation of each number wheel but as will noted this rotation takes place in the reverse direction to that which occurs when addition is being performed." Finally when the sectors have been returned the plate E is moved up so as to bring the pinion G once more into engagement with the outer sector A.

If a carry is necessary this is effected as the sector levers C C are returned to their zero positions. If no carry occurs then the limit of the movement of each of .these levers, when it is pushed back towardsthe completion of the cycle by the bar K, isdetel-mined by the sector lever projection C coming in Contact with the carry lever projection H. If, however, in the process of .proj ection returnin a sector lever it causes the rotation of its number Wheel beyond a carry point the carry lever H is released and drops in the manner described and then as the sector levers are pushed back the sector lever in the unit of next highest denomination,

into which number wheel the carry is to take place, is free to be moved by means hereinafter set forth further back than would otherwise be possible because the carry leve H has now been removed from the path of this sector lever projection C. The result is that the number wheel which is being rotated by the movement of this sector lever receives a further rotation to the extent of one integer. The operation is the same whether addition or subtraction is being performed. The actuating mechanism is so arranged that at the commencement of a cycle the plate E is moved from its extreme upper position and the pinion G taken out of engagement with the toothed sector A before the carry levers are reset, since in the process of this resetting, as already described, the sector lever C C is moved forward into its true zero position and this movement must not be imparted to the number wheel.

Provision is made for returning all the number wheels to zero so as to clear the machine in order to start a fresh series of operations. By suitable manipulation of the actuating mechanism, which will be described hereafter, this clearing is effected in the following. way :.-In the first rocking the-shaft F the plate E is lowered into its intermediate position and while in this position all the carry levers are reset. Next the plate E is raised so as to bring the pinion G into engagement with the rack A. The bar Know moves away so as to release the sector levers C C which all fall forward and in so doing rotate the several pinions G and number wheels. The extent to which each .of the sector levers can move in this case is determined by the detent lever G the end of which strikes the plate D and prevents further rotation of the number Wheel when it has reached its zero position. The plate E is .now again lowered into its intermediate position and eachsector lever C C is raised by the bar K, the return movement of the sectors in this case, as will be noted, having no effect on the number wheels. When the sectors are all in their zero positions the plate E is. again raised bringing the pinion G once more into engagement with the sector A so that at the end of the cycle the parts are in their respective positions in readiness for the commencement of a new operation. The number wheels are now all at zero as also the sectors C.

It will be apparent that when a carry takes place some device is necessary to perplace by Y mit the sector lever C C in the unit mechanism into which the carry is efi'ected to be moved back by the bar K the requisite dis tance equivalent to one integer beyond the other sectors which are simultaneously lifted by this bar K. The device conveniently used for this purpose is illustrated in Figure 9 which shows a portion of one sector lever C C and the manner in which the bar K acts thereon. Each lever C C as already mentioned is loosely mounted on the shaft C Adjacent to each lever C C and also loosely mounted on the shaft C is a twoarmed lever of which one arm L lies beside the part C of the sector lever while the other arm L is formed as a curved finger rearwardly and upwardly directed. A slot L is formed in the lever L towards its free end and this lever also carries a laterally projecting arm L Projecting from the side of the part C of the sector lever is a pin C having a squared end C which lies in the slot L A spring L is connected at one end to the lateral arm L and at the other to the pin C. A spring L is attached at one end to the lever L and at the other to some fixed part of the frame, this spring tending to move the lever L in a forward direction that is to say towards the bar K.

The parts are shown in Figure 9 in their true zero positions with the sector lever projection C engaged by the carry lever projection H and'the bar K in its raised position bearing against the lever L. If the pressure which the bar K exerts on the lever L is removed it will be seen that the levers L and C C will move relatively to one an other by reason of the action of the spring L the extent of this relative movement being determined by the dimensions of the slot L". Thus when the bar K has moved away and the lever C C is free to fall forward the pin C is at the end of the slot L opposite to that at which it is shown in Figure 9. The two levers Land C C maintain these relative positions until when the bar K once morelifts the levers the sector projection C strikes the carry projection H. The return movement of the lever C C is then checked but the lever L can still be moved further back by the bar K the extent of this movement as before being determined by the dimensions of the slot L. If, however, a carry has to be effected into the unit mechanism of which this sector lever forms part, then as already xplained the release of the carry lever H will have moved the projection H out of the path of the sector lever projection C. As the bar K now raises the levers the absence of the projection H will allow the sector lever C C to be moved further back and the levers will come to rest with the. end of the pin C at the rearward end of the slot L as when the sector lever C C is falling or in the process of being raised. Thus at the conclusion of the raising of the lever C C there will now be no relative movement between this lever and the lever L. In this way the over movement of the sectors carried by the lever C C is obtained and the number wheel rotated by the return of the sector lever receives the necessary extra rotation to the extent of one integer required to effect the carry. As will be seen the arrangement is such that under all ordinary circumstances the levers L and C C move and are moved and operate as one except when relative movement between these levers is brought about by contact between the carry lever projection H and the sector lever projection C.

The desired effect may be obtained with constructions other than that just described and such another construction is in fact conveniently employed in the case of the sector lever comprised in the unit mechanism of highest denomination. In the present machine this unit mechanism deals with thousands of pounds and the modified construction for permitting the over movement of the sector lever is shown in Figure 10. Here in place of the separate leve L L a small bell crank lever L L is pivotally mounted at L on the side of the lower part C of the sector lever. The range of movement of the bell crank lever L L" is determined by the pin C which projects from the side of the lever C and engages the slot L in the same way as the corresponding parts employed in the construction shown in Figure 9. A spring L connects the arm L with the lever C. The bar K strikes the lever L and when the carry lever projection H is presented to the sector lever projection C the spring L allows the lever L L to yield during the last part of the lifting movement of the bar K. It a carry is to take place and the projection H is removed from the path of the projection C then the lever C C moves to the full extent possible without relative movement takin place between this lever and the lever L T The means by which an item is initially fed into the machine can vary according to the way in which it is intended to employ the machine. The feeding in mechanism however must be so constructed and arranged that as indicated the movement of the sector levers can be determined'in accordance with the value of the integers in the item. A device whichmay be employed for the feeding in mechanism is shown in Figure 2 and comprises a series of tern lates conveniently in the form of discs which are all mounted on a common shaft N carried on fixed brackets forming part of th framing 0. A template disc M forms part of each unit mechanism and each template is cut with a series of steps M each step having a different radial length. Each template 

